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Hobo U20L-04 – Onset
Water level data logger (to a depth of 4 meters), data offload via the BASE-U-4 optical USB station or the U-DTW-1 waterproof shuttle
The Hobo U20L-04 is a low-cost, research-grade water level data logger for continuously measuring water level and temperature in a wide range of underwater environments. It features 0,1% accuracy, a polypropylene housing for use in both fresh and salt water, and a non-vented design for convenient and hassle-free deployment. This data logger requires either the U-DTW-1 waterproof shuttle or the BASE-U-4 base station for configuration and data offload, HOBOware software (free download). NOTE: HOBOware Pro is required when using the U-DTW-1 waterproof shuttle.
The housing is made of a self-contained non-vented design, that enables easy deployment. It is ideal for use in both fresh and saltwater environments, including wells, streams, lakes, wetlands and tidal areas. With depths up to 4 meters.
The durable ceramic pressure sensor withstands freezing and the HOBOware Pro software provides easy conversion to accurate water level reading, fully compensated for barometric pressure, temperature and water density.
Note: A calibration certificate is not offered for this logger. If you require a NIST-traceable calibration certificate, please see the U20-001-02 (freshwater) or U20-001-02-Ti (saltwater).
This data logger operates in outdoor and water environments and the U20L-04 data logger supports the following measurements: absolute pressure, barometric pressure, temperature and water level.
Technical specifications
Pressure and water level operation range: 0 to 145 kPa: approximately 0 to 4 meters of water depth at sea level, or 0 to 7 meters of water at 3.000 meters of altitude
Factory calibrated range: 69 to 145 kPa, 0° to 40°C
Burst pressure: 310 kPa or 18 meters of depth
Water level accuracy: ±0,1% FS, 3,0 cm water
Temperature operation range: -20° to 50°C
Accuracy: ±0,44°C from 0° to 50°C
Stability (drift): 0,1°C per year
Battery: 2/3 AA, 3,6 Volt lithium, factory-replaceable
Battery life: 5 years with 1 minute or greater logging interval
Memory (non-volatile): 64K bytes memory (approximately 21.700 pressure and temperature samples)
Launch modes: immediate start and delayed start
Offload modes: offload while logging: stop and offload
Battery indication: battery voltage can be viewed in status screen and optionally logged in datafile. Low battery indication in datafile.
Environmental rating: IP68